DENR Information Sheet Template

Australian sea lions Australian sea lions (Neophoca cinerea) are part of a group known as ‘eared’ seals. A male (bull) sea lion has brown fur and a blonde mane and can weigh up to 300kg, while the female (cow) weighs less than a quarter of this weight and has a light brown back and yellow belly. It is an ‘eared’ seal, as can be seen by its ear flaps. It differs from earless or ‘true’ seals such as leopard seals, which have no external ear flaps and cannot use their hind legs when on land. Pups can be born at any time of the year after an 18-month gestation – the longest of any type of seal. The mothers nurse their young for at least 18 months after they are born. Australian sea lions are listed as rare on the IUCN Red List. They are also listed as endangered under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999, and are protected in South Australia under the National Parks and Wildlife Act 1972. Commonly asked questions Where are Australian sea lions found? Sea lions are unique to South Australia and Western Australia. The population is about 15,000 animals, with 80 percent of sea lions located in South Australia. In South Australia, there are 39 breeding colonies, but most are very small and some of these are at risk of becoming extinct because each breeding colony is a closed population. Large colonies exist at Dangerous Reef in the Spencer Gulf, Seal Bay on Kangaroo Island and The Pages. There are smaller colonies on the West Coast and in the Great Australian Bight. What do they eat? Sea lions feed from the sea floor, catching cryptic creatures such as octopus, cuttlefish, small rays, sharks and rock lobster. Do they eat penguins? Sea lions are known to eat seabirds, but they primarily hunt on the sea floor, rather than catching surface-dwelling animals such as penguins. Are their numbers decreasing? Australian sea lions were hunted heavily during the 19th century for their fur and oil and the population has never returned to its pre-hunting levels. Sea lions are now most at risk from the gill nets used by some sectors of the fishing industry. The colony at Seal Bay is declining, though it still has more than 1300 animals. The Pages colony is stable. Dangerous Reef is the only sea lion colony that is increasing in size. Are they competing with fur seals for food? No, fur seals and sea lions are not in direct competition for food. Fur seals mostly feed from the top of the ocean where they take fast moving fish. Sea lions are bottom feeders and eat slow moving creatures such as cuttlefish, mullet and small rays. Is there research being done into their declining populations? There are regular surveys of sea lion populations. The surveys are invaluable as a comparison between seasons and a barometer of how the populations are faring. The major causes of death of sea lion pups is accidental crushing by adults (particularly fighting juvenile males) and deliberate attacks by sub-adult males. It is normal for one third of sea lion pups to die before weaning. Hookworms may also have an impact but the significance of these parasites is not yet clear. The major cause of death of adults has been gill nets. Is the impact of gill netting being managed? Gill net closures came into effect in the Seal Bay area in July 2010. These closures protect about half of the foraging zone of female sea lions. The gill net fishery closure has not yet been in place long enough to gauge the influence on pupping rates. These closures do not free up food for sea lions, but they reduce the chance that a female will drown in a gill net. If more females survive as a result of the gill net closure, this will lead to increase in the number of pups being born over the long term. .

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